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Difficulty: MediumPharmacologic Interventions

A 65-year-old African American man comes to the clinic for follow-up of heart failure. He was hospitalized 4 weeks ago for acute decompensated heart failure, and an echocardiogram at that time showed a left ventricular ejection fraction of 30%. His past medical history includes type 2 diabetes mellitus, hyperlipidemia, and bilateral renal artery stenosis that was diagnosed via magnetic resonance angiography two years ago. His current medications include carvedilol, furosemide, and atorvastatin. His blood pressure is 146/92 mm Hg and his pulse is 68/min. Physical examination shows a regular heart rate, clear lungs to auscultation, and no peripheral edema.

Laboratory studies reveal a serum sodium of 138 mEq/L, serum potassium of 4.2 mEq/L, blood urea nitrogen of 18 mg/dL, and serum creatinine of 1.1 mg/dL.

The physician discusses initiating an additional medication to optimize his guideline-directed medical therapy. Which of the following medications is absolutely contraindicated in this patient?

  1. LisinoprilAnswer
  2. B
    Hydralazine
  3. C
    Isosorbide dinitrate
  4. D
    Empagliflozin
  5. E
    Digoxin

Answer

Lisinopril is absolutely contraindicated in this patient.
Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor. In patients with bilateral renal artery stenosis, renal perfusion is chronically compromised. The kidneys compensate by upregulating the renin-angiotensin-aldosterone system (RAAS). Angiotensin II preferentially constricts the efferent arteriole, which helps maintain intraglomerular pressure and the glomerular filtration rate (GFR). Administering an ACE inhibitor abruptly removes this compensatory efferent vasoconstriction, leading to a precipitous drop in GFR and potentially irreversible acute renal failure. Therefore, ACE inhibitors and angiotensin II receptor blockers (ARBs) are absolutely contraindicated in these patients. For this patient, the combination of hydralazine and isosorbide dinitrate would be the preferred alternative for afterload and preload reduction to improve long-term survival.

Step-by-Step Solution

1
Identify the patient's primary condition and treatment goal.
The patient has heart failure with reduced ejection fraction (HFrEF) and requires optimization of guideline-directed medical therapy.
To determine which drug classes are typically indicated for improving survival.
2
Analyze the patient's comorbidities for potential absolute contraindications.
The patient has a known history of bilateral renal artery stenosis.
Comorbidities heavily influence medication safety profiles, particularly in heart failure management where therapies often affect renal hemodynamics.
3
Evaluate each medication option against the identified comorbidity.
Lisinopril (an ACE inhibitor) blocks angiotensin II, which is required to maintain glomerular filtration rate in the setting of bilateral renal artery stenosis.
To isolate the medication that is strictly contraindicated and could cause severe patient harm.

Key Concept

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) are absolutely contraindicated in patients with bilateral renal artery stenosis due to the risk of precipitating acute renal failure.
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Pharmacologic Interventions

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